Referenced in: none

Automatically associated channels: Kv12.1

Title: Cloning of the human TASK-2 (KCNK5) promoter and its regulation by chronic hypoxia.

Authors: Stephen P Brazier, Helen S Mason, Alan N Bateson, Paul J Kemp

Journal, date & volume: Biochem. Biophys. Res. Commun., 2005 Nov 4 , 336, 1251-8

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/16168386

Abstract
The tandem P domain potassium channel family includes five members of the acid-sensing subfamily, TASK. TASK channels are active at resting potential and are inhibited by extracellular protons, suggesting they function as acid sensors and control excitability/ion homeostasis. Indeed, TASK-2 (KCNK5) has been shown to control excitability, volume regulation, bicarbonate handling, and apoptosis in a variety of tissues. With such diverse functions being ascribed to TASK-2, it is important to understand long-term as well as short-term regulation of this important channel. Thus, we have cloned the TASK-2 promoter, demonstrated that its transcriptional activity is dependent upon pO(2), shown that deletion of overlapping consensus binding sites for NF-kappaB/Elk-1 ablates this O(2) sensitivity, and proved that Elk-1 binds preferentially to this site. Furthermore, the consequences of chronic hypoxia on natively expressed TASK-2 are decreased steady-state mRNA and cell depolarization showing that TASK-2 contributes to the excitability of this important lung cell type.